10,269 research outputs found
Resolving Gas Flows in the Ultraluminous Starburst IRAS23365+3604 with Keck LGSAO/OSIRIS
Keck OSIRIS/LGSAO observations of the ultraluminous galaxy IRAS~23365+3604
resolve a circumnuclear bar (or irregular disk) of semimajor axis 0.42" (520
pc) in Paschen-alpha emission. The line-of-sight velocity of the ionized gas
increases from the northeast toward the southwest; this gradient is
perpendicular to the photometric major axis of the infrared emission. Two pairs
of bends in the zero-velocity line are detected. The inner bend provides
evidence for gas inflow onto the circumnuclear disk/bar structure. We interpret
the gas kinematics on kiloparsec scales in relation to the molecular gas disk
and multiphase outflow discovered previously. In particular, the fast component
of the outflow (detected previously in line wings) is not detected, adding
support to the conjecture that the fast wind originates well beyond the
nucleus. These data directly show the dynamics of gas inflow and outflow in the
central kiloparsec of a late-stage, gas-rich merger and demonstrate the
potential of integral field spectroscopy to improve our understanding of the
role of gas flows during the growth phase of bulges and supermassive black
holes.Comment: 14 pages with 7 figures accepted to the astrophysical journa
Prehistoric psychotropic consumption in Andean Chilean mummies
Hallucinogenic plants are often regarded as the main source of psychoactive drugs in antiquity to reach deep altered states of consciousness^1,2^. Many researchers believe this was particularly true during the Tiwanaku empire expansion, circa (500-1000 A.D.), along the Atacama Desert of Chile. Highly decorated snuffing tablets and tubes are often found as grave goods during this period^3,4,5,6,7,8^. Until now the type of drugs consumed in this paraphernalia has been unclear. From the modern city of Arica, naturally mummified human bodies with abundant hair provided a unique opportunity to test for hallucinogenic plants consumed in Andean prehistory. Analysis by gas chromatography and mass spectrometry demonstrated the presence of harmine. The Banisteriopsis vine, commonly called Ayahuasca, was the probable source. This is the first confirmed evidence of psychoactive plant consumption in pre-Hispanic Andean populations along the Atacama coastal region. Of the 32 mummy hair samples analyzed 3 males tested positive for harmine. This alkaloid aids in the catalysis and synergic effects of powerful hallucinogenic drugs. The consumption of harmine was likely related to medicinal practices and not exclusively ingested by shamans. Another important aspect of this evidence is that Banisteriopsis is an Amazon plant. It does not grow in the Atacama coastal region. Thus, our findings reveal extensive plant trade networks in antiquity between the coast, desert, highlands, and Amazon basin. The excellent preservation of human organic specimens, the use of gas chromatography and mass spectrometry allowed us to map and demonstrate the consumption of psychoactive compound plants in Andean prehistory. In addition, our findings open the door for future studies to debate the consumption and social role of ancient psychoactive and hallucinogenic plants
An Analysis of Potential Tax Incentives to Increase Charitable Giving in Puerto Rico
Compares options for improving tax incentives for charitable giving, including lifting the ceiling on deductions as a percentage of adjusted gross income, and estimated effects on nonprofits in Puerto Rico, where average giving is high relative to AGI
Intrinsic Spectral Geometry of the Kerr-Newman Event Horizon
We uniquely and explicitly reconstruct the instantaneous intrinsic metric of
the Kerr-Newman Event Horizon from the spectrum of its Laplacian. In the
process we find that the angular momentum parameter, radius, area; and in the
uncharged case, mass, can be written in terms of these eigenvalues. In the
uncharged case this immediately leads to the unique and explicit determination
of the Kerr metric in terms of the spectrum of the event horizon. Robinson's
``no hair" theorem now yields the corollary: One can ``hear the shape" of
noncharged stationary axially symmetric black hole space-times by listening to
the vibrational frequencies of its event horizon only.Comment: Final version with improved abstract, updated references, corrected
typos, and additional discussio
One-Year Effects of Project EX in Spain: A Classroom-Based Smoking Prevention and Cessation Intervention Program.
BackgroundTobacco use prevalence rates are high among Spanish adolescents. Programming to counteract tobacco use is needed.Methods and findingsThe current study provides a one-year follow-up outcome evaluation of Project EX, an eight-session classroom-based curriculum. The intervention was tested using a randomized controlled trial with 1,546 Spanish students, involving three program and three control schools. Compared to the control condition, the program condition revealed a greater reduction in nicotine dependence (p < .05) and CO ppm levels (p < .001), and lower consumption of cigarettes at last month (p = .03).ConclusionsLong-term outcomes of the Project EX classroom-based program are promising for adolescent prevention and possibly cessation in Spain
ZAP -- Enhanced PCA Sky Subtraction for Integral Field Spectroscopy
We introduce Zurich Atmosphere Purge (ZAP), an approach to sky subtraction
based on principal component analysis (PCA) that we have developed for the
Multi Unit Spectrographic Explorer (MUSE) integral field spectrograph. ZAP
employs filtering and data segmentation to enhance the inherent capabilities of
PCA for sky subtraction. Extensive testing shows that ZAP reduces sky emission
residuals while robustly preserving the flux and line shapes of astronomical
sources. The method works in a variety of observational situations from sparse
fields with a low density of sources to filled fields in which the target
source fills the field of view. With the inclusion of both of these situations
the method is generally applicable to many different science cases and should
also be useful for other instrumentation. ZAP is available for download at
http://muse-vlt.eu/science/tools.Comment: 12 pages, 7 figures, 1 table. Accepted to MNRA
Mobility through Heterogeneous Networks in a 4G Environment
Serving and Managing users in a heterogeneous environment. 17th WWRF Meeting in Heidelberg, Germany, 15 - 17 November 2006. [Proceeding presented at WG3 - Co-operative and Ad-hoc Networks]The increase will of ubiquitous access of the users to the requested services points towards the integration of heterogeneous networks. In this sense, a user shall be able to access its services through different access technologies, such as WLAN, Wimax, UMTS and DVB technologies, from the same or different network operators, and to seamless move between different networks with active communications. In this paper we propose a mobility architecture able to support this users’ ubiquitous access and seamless movement, while simultaneously bringing a large flexibility to access network operators
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